Device for inserting filament into a radially clamping grip

ABSTRACT

A TOOL FOR THREADING A RADIALLY CLAMPING GRIP WITH A LEADER YARN BY DIRECTING THERETHROUGH A FLUID FLOW UNDER PRESSURE. A SUCTION TUBE INSERTED INTO THE GRIP SEPARATES THE CLAMPING MEMBERS FOR REMOVAL OF BROKEN YARN AND THE INSERTION OF THE LEADER END OF SPUN YARN.

Sept. 20, 1971 N RD Em. 3,605,396

DEVICE FOR INSERTING FILAMENT INTO A RADIALLY CLAMPING GRIP Filed Dec. 2, 1969 3 Sheets-Sheet 1 FIG. 1/

Sept. 20, 1971 c, GLHGNARD EIAL 3,605,396

- DEVICE FOR INSERTING FILAMENT INTO A RADIALLY Y CLAMPING GRIP Filed Dec. 2, 1969 3 Shuts-Shoot 2 FIG. 5

FIG. 4

FIG. 3

P 20, 1971 c. GUIGNARD ETAL 3,605,396 DEVICE FOR INSERTING FILAMENT INTO A RADIALLY CLAMPING GRIP 3 Shoots-Shoot 3 Filed Dec. 2, 1969 mm W w n NM NM United States Patent O 3,605,396 DEVICE FOR INSERTING FILAMENT INTO A RADIALLY CLAMPIN G GRIP Claude Guignard, Ferney-Voltaire, France, and Jean Chatelaine Pellaton and Maurice Poull, Meyrin, Switzerland, assignors to Electrospin Corporation, Columbus, Ohio Filed Dec. 2, 1969, Ser. No. 881,357 Claims priority, application Switzerland, Dec. 24, 1968, 19,255/ 68 Int. Cl. D0111 15/00, 13/04; D01g 23/08 US. Cl. 57--106 14 Claims ABSTRACT OF THE DISCLOSURE A tool for threading a radially clamping grip with a leader yarn by directing therethrough a fluid flow under pressure. A suction tube inserted into the grip separates the clamping members for removal of broken yarn and the insertion of the leader end of spun yarn.

BACKGROUND OF THE INVENTION The present invention relates to a device for inserting a yarn into a radially clamping grip at the time of startup or in piecing up after a yarn break.

When manufacturing or handling yarn, it is often necessary to insert the end of the yarn into a radially clamping grip. This is the case, for instance, in the manufacture of yarn by the so-called open-end spinning methods among which is the electrostatic spinning method which forms the subject of US. Pat. 3,411,284. According to this method, fibers are electrically charged and conveyed individually by electrostatic attraction through an electrostatic field from a delivery member to a twisting member for forming into yarn. The twisting member in this instance comprises a rotating radially clamping grip which, while compelling the fibers which reach its inlet to twist together to form a yarn, enables them to slide axially therethrough as the yarn is produced. One example of a grip of this kind is shown in US. Pat. 3,372,537. Two problems arise with discontinuous spinning apparatuses provided with a twisting member having a radially clamping grip; that of inserting a leader yarn at the start-up of the apparatus, and that of reinserting the yarn in the event of yarn breakage during production. In either case the clamping elements of the grip must be expanded so as to open a passage through which the yarn may be passed, either by drawing it through the grip from the inlet end or from the outlet end.

SUMMARY OF THE INVENTION The present invention provides a simple device for performing the above operation without complicated actions and with means which can readily be automated. The device comprisese a suction tube and a propulsion tube, one of the ends of the latter being intended for connection to a source of fluid under pressure and the other end forming an ejection nozzle for the fluid. The two tubes are secured together in a relative position such that the negative pressure set up by the flow of fluid out of the ejection nozzle generates in the suction tube an airflow in the same direction as the fluid flow, the pressure of the fluid being such that the airflow is able to entrain the yarn through the suction tube by aspiration.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described by reference to a preferred embodiment thereof and three modifications as shown in the accompanying figures of drawing, wherein:

Patented Sept. 20, 1971 FIG. 1 is a plan view of a preferred embodiment,

FIGS. 2 to 5 illustrate the manual operation of the device according to one embodiment by showing four successive positions it will occupy in relation to a radially clamping grip,

FIG. 6 shows a plan view of a first modification constituting the preferred embodiment,

FIGS. 7 to 9 illustrate the sequential positions occupied by the modification in FIG. 6,

FIGS. 10 and 11 are plan views of two other modifications.

DESCRIPTION OF THE PREFERRED EMBODIMENT Now referring to FIG. 1, the inserting device comprises a cylindrical suction tube 1 open at its two ends, a rear or aspiration end 2 and a front end 3, and a propelling tube 4 which extends into the suction tube 1. Propelling tube 4 has two ends 5 and 6 of which the first, i.e. the inner end 5, is located between the ends 2 and 3 of the suction tube 1, and of which the second, i.e. the outer end 6, is intended to be connected by a flexible tube 7 to a source of fluid under superatmospheric pressure (not shown). Propelling tube 4 therefore extends laterally through the -wall 8 of suction tube 1 and is bent so that the fluid under pressure may be injected in a direction parallel to the axis of suction tube 1, as indicated by the arrow 9, the end 5 serving as a nozzle for ejecting the fluid. The end 5 is radially offset from the axis of suction tube 1 so as to clear, to the greatest possible extent, the internal through flow cross-section of tube 1. The propelling tube 4 can be secured in fluidtight relation to the suction tube wall 8 by any known means, preferably by welding or adhesive bonding.

The pressure of the fluid ducted by the flexible tube 7 is so chosen that the jet of fluid produces by a Venturi effect a negative or subatmospheric pressure in the suction tube 1 in the region of the inner end 5, which negative pressure causes outside air to be sucked in through the rear end 2 and to be ejected through the front end 3. If the front end 3 were to be closed off, for instance, by being covered with a finger, as shown in FIGS. 2 and 3, the intake of outside air would cease and instead fluid would be discharged through the rear end 2, as indicated by arrows 12 and 13 in FIGS. 2 and 3; the tube 1 then has a blowing action via its rear end 2.

The operation of this device, generally designated 10, is illustrated by FIGS. 25 where it has been assumed that the device is being used to insert a yarn into a radially clamping grip, generally designated 20' such as is described in US. Pat. 3,372,537. The grip 20 comprises a bundle of resilient filaments 21 which is surrounded by a damping sleeve 22, the filaments 21 each have a bent portion so as to form a bow-net 23, which is secured to a crown 24 whose inner configuration is flared to form an inlet funnel 25. The Whole is housed in a cylindrical body 26 formed with an outlet orifice 27. In electrostatic or other kinds of open-end spinning, the grip 20 is rotatably driven around the axis of the bundle of filaments 21; it receives, at its inlet 25, fibers which are conveyed thereto individually and it delivers, at its outlet 27, a spun yarn resulting from the twisting of these fibers.

Referring to FIGS. 25, assume that the yarn 30 has broken and remains supported by any retaining member, e.g. an eye 31, so that a piece 32 of yarn remains gripped in the bundle 21 of resilient filaments. The spinning of the grip 20 is stopped, the device 10 is then held between the thumb 33 and the middle finger 34, while the index finger 35 blocks the front end 3 (FIG. 2). Under these conditions, the fluid under pressure, which will be assumed to be compressed air, cannot produceany suc tion effect through the suction tube 1; instead, air is discharged through the rear end 2. The device 10 is then introduced into the stationary grip 20 through the inlet 25 thereof (FIG. 3), the rear end 2 of the suction tube 1 radially expanding the aperture through the center of the resilient filaments of the bundle 21. The piece of yarn 32 is thereby released and under the action of the discharged air, it is expelled from the grip 20. When the rear end 2 of the suction tube passes beyond the outlet 27 of the grip and comes near the end of the yarn 30 (FIG. 4), the index finger 35 is raised to unblock the front end 3; air is sucked in and entrains with it the yarn 30, causing it to move forward in the suction tube 1 toward the front end 3. With air still flowing upwardly through tube 1 to entrain the yarn 30, the device 10 is then extracted upwardly from the grip 20 (FIG. 5) so that the bundle 21 closes on the yarn 30 in a reinserted position, rotation of the grip 20 is reestablished and twisting is resumed.

With the embodiment just described, the device must be introduced through the inlet funnel 25 of the grip and once it has served its purpose it becomes completely free again and can be used elsewhere to insert another yarn into another grip.

The modification shown in FIG. 6 can be inserted only via the rear of the grip, that is from beneath it. This second embodiment differs from the previous one as follows; the propelling tube 4a instead of being bent at right-angles, is bent obliquely for reasons of space and the rear end 2a of the suction tube It: is provided with an intake funnel 36. The propelling tube 4a may be secured to the wall 8a of suction tube 1a in any desired manner as in the first embodiment. For this embodiment to be usable, the grip must be such as to allow insertion of the suction tube 1a through the outlet of the grip. In FIG. 7 each filament of the bunch 21a is shown with an outwardly directed bend to form an outlet bow-net 37. A grip of this configuration is shown and fully described in copending application Ser. No. 877,993, filed Nov. 19, 1969, and now Pat. No. 3,583,141 entitled Radially Clamping Grips. In this second embodiment, the front end 3a of suction tube 1a stays permanently open so as to eject air continuously in operation. The broken piece 32 of yarn is expelled through the inlet of the grip when the front end 3a of suction tube In prizes apart the resilient filaments of the bundle 21a (FIG. 8). When the yarn 30 appears at the inlet a of the grip, the device is withdrawn (FIG. 9) and the supply of fluid under pressure is interrupted. The yarn is thus reinserted in the grip and the operation can resume. With this modification the yarn 30 extends through the inserting device permanently so the latter cannot be used elsewhere; it remains associated with its corresponding grip, however, since the front end 3a does not have to be blocked and unblocked, it is very suitable for automatic operation. With this modification each grip is provided with an individual insertng device.

FIG. 10 shows a modfication of that shown in FIG. 6 with the propelling tube 4a extending into the suction tube 1a through the rear end 29 rather than through the wall 8a. The operation of this modification is similar to that shown in FIG. 6.

In FIG. 11 a further modification is shown where operation is similar to the preferred embodiment of FIG. 1 and permits introduction of the device only through the front end 25 of the grip. This modification differs only in the relative positions of the suction tube 11; and of the propelling tube 4b. Whereas in the preferred embodiment, it is the propelling tube 4 which extends into the suction tube 1 (FIG. 1), here it is the opposite, and the front end 3b is placed very near the ejection nozzle 5b.

Whatever the constructional form, compressed air is advantageously used as the fluid under pressure although, of course, any other gas may be suitable. Also, a liquid under pressure, e.g. water, can be used in special cases; the device then operates like a water aspirator which 4 sucks the yarn which it is required to insert into the grip.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. For use in an open-end spinning apparatus in which yarn is spun by feeding individual fibers to an end of a yarn held in a rotating yarn grip which resiliently grips such yarn as it is being spun, said grip having a radially expansible and contractible through aperture and through which the yarn is axially drawn, a device for inserting into the through aperture of said grip an end of a yarn to which individual fibers can be fed, said device comprising:

(a) means for expanding said grip aperture to a diameter greater than that of the yarn being spun,

(b) means for feeding an end of a spun yarn into said aperture while so expanded and axially retaining the yarn in said aperture while permitting said aperture to contract and grip the yarn.

2. A device as set forth in claim 1 wherein said means for feeding an end of a spun yarn into said aperture includes means for entraining the yarn by movement of a fluid under pressure.

3. For use in an open-end yarn spinning apparatus having a rotatable radially clamping yarn grip, a device for reinserting a yarn end into said grip, comprising (a) a suction tube having an internal cross section greater than that of the yarn being spun and an external cross section sufliciently small that it can be inserted coaxially into and radially expand said grip sufliciently to permit passage of the yarn therethrough,

(b) a propulsion tube having one end for connecting to a source of fluid under pressure and a second end forming an ejection nozzle for the fluid,

(c) said suction tube and said propulsion tube being secured to one another in a relative position such that the negative pressure set up by the flow of the fluid out of said ejection nozzle generates in the suction tube an air flow in the same direction as the fluid flow, and

(d) the pressure of the fluid being such that the air flow is able to entrain the yarn through said suction tube by aspiration.

4. A device as set forth in claim 3 wherein said propulsion tube extends into said suction tube through the side Wall thereof.

5- A device as set forth in claim 3 wherein said suction tube has an aspiration end, and wherein said propulsion tube extends into said suction tube through said aspiration end.

6. A device as set forth in claim 4 wherein the portion of said propulsion tube which is located inside said suction tube is placed in contacting relationship with the inside surface of the suction tube side wall so as to be offset from the suction tube axis.

7. A device as set forth in claim 5 wherein the portion of said propulsion tube which is located inside said suction tube is placed in contacting relationship with the inside surface of the suction tube side wall so as to be offset from the suction tube axis.

8. A device as set forth in claim 5 wherein said suction tube is provided with a funnel at said aspiration end.

9. A device as set forth in claim 3 wherein said suction tube extends into said propulsion tube through the sidewall thereof, one end of said suction tube being placed near said ejection nozzle.

10. A device as set forth in claim 3 wherein said fluid under pressure is compressed air.

11. A method of piecing up yarn in a radially clamping grip which includes resilient filaments from the inlet end, which comprises:

(a) forcing the resilient filaments apart radially,

(b) directing a flow of compressed air through the grip toward the outlet end to clear the passage,

(c) reversing the direction of the flow of air to pick up and draw in the loose end of yarn, and

(d) releasing the resilient filaments to entrap yarn.

12. A method of piecing up yarn in a radially clamping grip as set forth in claim 11, wherein the resilient filaments are forced apart by inserting a hollow tube into the grip through the inlet bow-net.

13. A method of piecing up yarn in a radially clamping grip which includes resilient filaments from the outlet end, which comprises (a) forcing the resilent filaments apart radially,

(b) directing a continuous fiow of compressed air through the grip toward the inlet end for clearing the passage and for carrying in the loose end of yarn,

(c) introducing the loose end of yarn into the flow of air, and

(d) releasing the resilient filaments to entrap yarn.

14. A method of piecing up yarn in a radially clamping grip as set forth in claim 13, wherein the resilient filaments are forced apart by inserting a hollow tube into the grip through the outlet end of the grip.

References Cited UNITED STATES PATENTS 1,671,785 5/1928 Rushton 5734.5 2,681,729 6/1954 Griset 5734.5 2,724,957 11/1955 Griset 22691X 3,094,262 6/1963 Ashby et a1 5734.5X 3,151,021 9/1964 Balch 57106X 3,241,234 3/1966 Kiefer et a1. 5734.5X 3,333,407 8/1967 Bruin et al. 57106X 3,372,537 3/1968 Poull et a]. 5759 3,452,626 7/1969 Speakman 5734.5X 3,475,891 11/1969 Matsuoka et a1. 5734.5X

DONALD E. WATKINS, Primary Examiner U.S. Cl. X.R.

Dedication 3,605,396.-0Zaude Guz'gnam, Ferney-Voltaire, France, and Jean Pellaton,

Chatelaine, and Maurice Poull, Meyrin, Switzerland. DEVICE FOR IN SERTIN G FILAMENT INTO A RADIALLY CLAMPING GRIP. Patent dated Sept. 20, 1971. Dedication filed Mar. 23, 1977,

by the assignee, Electmspz'n Corporation.

Hereby dedicates to the Public the entire term of said patent.

[Ofioial Gazette May 10, 1.977.] 

